Abstract: The controlled pre-rolling of a slab, leaving a continuous casting plant is carried out with pairs of pre-rolling elements (14, 114, 16) assembled in at least one pre-rolling assembly (10), the first of these pre-rolling assemblies (10) being positioned immediately downstream of the foot rolls (12) of a crystalliser (11). At least one data processing and controlling unit (21) governs the positioning and the adjustment of the pre-rolling elements (14, 114, 16), the final pre-rolling zone being pre-defined by a specific pair (No.

Abstract: Method and continuous casting line for the continuous casting advantageously, but not only, of long products such as billets or blooms, whereby the solidification of the cast product (16) is completed at a position downstream of the outlet of the mould (13) and whereby the cast product (16) leaving a continuous casting machine (11) curving at a speed of at least 4 mts/min.

Abstract: Discharge nozzle (10) for continuous casting of slabs having narrow sides between about 30 and about 300 mm.

Abstract: Method for the continuous casting of high-carbon steels to produce thin slabs, these steels being characterised by a content of carbon greater than 0.50%, in which method the taper of the mould at least in its first segment having to be between 1.5% and 4% per meter, the frequency of oscillation of the mould being between 180 and 350 oscillations per minute with a travel upwards and downwards of about .+-.5 to 9 mm., with a total travel of 10 to 18 mm., the cooling in the primary cooling period being very intense, the times of the transient state of start-up of the casting being reduced by 1/3 to 1/4 as compared to the normal times of the transient state of start-up.

Abstract: Method for the continuous casting of peritectic steels to produce thin slabs, these peritectic steels being characterised by a content of carbon between 0.10%, and 0.15%, and at times even between 0.09% and 0.16%, in which method the taper of the mould at least in its first segment is between 2.0% and 6% per meter and the frequency of oscillation of the mould should be between 300 and 500 oscillations per minute with a travel upwards and downwards between .+-.2.5 mm. and 4 mm., with a total travel of 5 mm. to 8 mm., the primary and secondary cooling being restricted.

Abstract: A circuit for reducing the voltage of a d-c power supply with one grounded terminal comprises a chopping transistor in an ungrounded supply lead, periodically turned on and off by an electronic switch, and an L/C network downstream of that transistor along with a flywheel diode. The switch lies in series with an ancillary voltage generator, having a terminal voltage substantially lower than the supply voltage, in a grounded loop which is reactively coupled to the transistor base via a capacitor or a transformer. A control signal for opening and closing the switch may be obtained from a square-wave generator connected across the transistor output and driven by the stepped-down supply voltage.

Abstract: An electronic circuit breaker feeding a d-c/d-c converter from a power supply common to several such converters includes a normally saturated main or switching transistor T.sub.1 in series with the associated converter, the latter having an output from which auxiliary voltage is fed back to an ancillary transistor T.sub.2 lying in series with a voltage divider R.sub.1, R.sub.2 serving to bias the main transistor into conduction. A further transistor T.sub.3 triggers the cutoff of the main transistor T.sub.1 when the converter draws excess current, part of which flows through the voltage divider R.sub.1, R.sub.2. Another voltage divider R.sub.4 R.sub.5 in parallel with the first-mentioned divider biases the further transistor T.sub.3 and is thus traversed by a portion of the feedback current passing through the ancillary transistor T.sub.2, being therefore likewise cut off upon de-energization of the converter by the cessation of conduction through the main transistor.